Buying Healthy Fish

How Can I Make Sure the Fish I Bring Home Are Healthy?


Once you have gone through the trouble to research and select the fish for your aquarium you want to make sure they are going to survive. The last thing you want to do is bring home sick fish that infect the other fish in your tank and end up dying in a matter of days after you bring them home. While there is no guarantee that the fish you purchase at the pet store are not carrying some kind of disease, you can do your best to select the healthiest fish available. Then, once you bring your fish home, there are a few precautions you should take to protect your other fish against infection.

Signs of a Healthy Fish

When you first arrive at the pet store spend a few minutes looking around at the tanks of aquarium fish. Check to see whether the tanks appear to be clean and well-maintained. There should be no algae build-up on the tank walls, the fish should all be active and there should not be clumps of dead fish floating around at the bottom of the tank or clustered near the filter. If you are not satisfied that the tanks are clean, do not risk purchasing your fish from that store. When fish are kept in unclean environments, the chances are good that they are already stressed or ill and bringing home one or more of these fish could just be asking for trouble.


Once you have examined the store itself and have determined that it is clean and well-stocked you can begin to look at individual fish. By the time you visit the pet store to make a purchase you should already have some idea which type of fish you want to buy. It is wise to do some basic research before purchasing fish to ensure that your tank is set up to meet the requirements of those fish and that the fish themselves are likely to get along. Locate the tanks housing the species of fish you intend to purchase and spend some time observing the specimens available.

Look for fish that are active and display good colouration. If you are purchasing marigold swordtails, for example, you should be looking for fish that display a bright orange colour – specimens that appear dull or pale may be suffering from illness. Healthy aquarium fish should appear lively, swimming around the tank without difficulty. Do not select fish that are laying on the bottom of the tank, gasping at the surface for air or those that appear to have difficulty swimming. You should also examine the fish for their physical health. Healthy aquarium fish will have clear eyes, intact fins and no visible swelling, discoloration or growths. If the fish in the tank meet all of these criteria, you can be reasonably assured that the fish are healthy enough to take home.

Tips for Introducing New Fish


No matter how careful you are to select aquarium fish that appear healthy, there is still a chance that the fish you bring home are carriers of disease. In order to prevent new fish from infecting your current tank inhabitants it is wise to quarantine the new fish for at least two weeks. You should always keep a quarantine/hospital tank prepared in the event that one of your fish falls ill or you bring home new specimens to add to your tank. Place the new fish in the quarantine tank and, over the next two weeks, observe them for signs of illness. The fish should continue to be active, should display a healthy appetite and should not develop any physical signs of illness. If, after the two week period, the fish still appear to be healthy you can safely add them to your established tank.

When adding new fish to your aquarium it is important not to rush the process. If the temperature or water chemistry in your established tank is vastly different from the tank at the pet store, your fish could suffer from shock or stress. To transition your fish safely into their new aquarium it is best to float the bags you brought your fish home in inside the established tank for at least half an hour. This will allow for the water temperature in the bag to slowly adjust to the temperature in the tank. You may also want to add a small amount of water from the tank to the bag so the fish can get used to any changes in water chemistry. Once the fish have been acclimated, carefully net them from the bag and release them into their new home.